Re: [Qemu-devel] [PATCH 3/3] s390x: Replace unchecked qdev_init() by qdev_init_nofail()

[Cornelia Huck]

On Wed, 18 Feb 2015 16:31:28 +0100
Cornelia Huck <address@hidden> wrote:

> > Markus Armbruster <address@hidden> writes:
> > 
> > > s390_flic_init() is a helper to create and realize either
> > > "s390-flic-kvm" or "s390-flic-qemu".  When qdev_init() fails, it
> > > complains to stderr and succeeds.
> > >
> > > Except it can't actually fail, because the "s390-flic-qemu" is a dummy
> > > without a realize method, and "s390-flic-kvm"'s realize can't fail,
> > > even when the kernel device is really unavailable.  Odd.
> 
> Yes, this _is_ odd. I'd say we'd want to die if we can't instatiate the
> kvm-flic, but at least for injecting interrupts we have a fallback to
> the old method (but looking at the code, this does not quite work out
> as I thought it would). The qemu-flic is really just a dummy.
> 
> > >
> > > Replace qdev_init() by qdev_init_nofail() to make "can't fail" locally
> > > obvious, and get rid of the unreachable error reporting.
> > >
> > > Cc: Christian Borntraeger <address@hidden>
> > > Cc: Cornelia Huck <address@hidden>
> > > Cc: Alexander Graf <address@hidden>
> > > Signed-off-by: Markus Armbruster <address@hidden>
> > > ---
> > >  hw/intc/s390_flic.c | 6 +-----
> > >  1 file changed, 1 insertion(+), 5 deletions(-)
> > >
> > > diff --git a/hw/intc/s390_flic.c b/hw/intc/s390_flic.c
> > > index 03c5e89..02e10b7 100644
> > > --- a/hw/intc/s390_flic.c
> > > +++ b/hw/intc/s390_flic.c
> > > @@ -30,7 +30,6 @@ S390FLICState *s390_get_flic(void)
> > >  void s390_flic_init(void)
> > >  {
> > >      DeviceState *dev;
> > > -    int r;
> > >  
> > >      dev = s390_flic_kvm_create();
> > >      if (!dev) {
> > > @@ -38,10 +37,7 @@ void s390_flic_init(void)
> > >          object_property_add_child(qdev_get_machine(), 
> > > TYPE_QEMU_S390_FLIC,
> > >                                    OBJECT(dev), NULL);
> > >      }
> > > -    r = qdev_init(dev);
> > > -    if (r) {
> > > -        error_report("flic: couldn't create qdev");
> > > -    }
> > > +    qdev_init_nofail(dev);
> > >  }
> > >  
> > >  static int qemu_s390_register_io_adapter(S390FLICState *fs, uint32_t id,
> 
> I think this is OK for the time being. We need to look into the various
> weirdnesses for the kvm-flic, though.
> 
> Acked-by: Cornelia Huck <address@hidden>

Applied to my s390-next tree.